The study of apoptosis pathway of colorectal cancer cells and the potential value of target treatment of colorectal cancer in future

Objective To understand which apoptosis pathway were more important in the course of colorectal cancer.Methods The colorectal specimens were collected from 60 cases of colorectal cancer patients(CRC group),18 cases of colorectal adenoma patients(CRA group) and 18 normal adults(control group).All the specimens were examined by in situ hybridization and immunohistochemical Max VisionTM methods for both the extrinsic and intrinsic apoptosis pathway,the extrinsic pathway by examination the FasL,Bid and the intrinsic pathway by cytochrome C mRNA(Cty c).Results The positive rate of FasL expression were 16.07%(9/56 cases) in colorectal cancer group(CRC-group),62.5%(11/18 cases) in normal adult(control group) and 50%(9/18 cases) in colorectal adenoma group(CRA group).The positive rate of Bid expression were 66.07%(37/56 cases) in CRC group,72.22 %(13/18 cases) in control group and 94.44%(17/18 cases) in CRA group.In colorectal cancer group the Bid expression of Dukes D stage was 100% while that in stage A and stage B were 38.1% and 40.00%,respectively.The differences were statistic significant.The intensity of expression of cytochrome C in low,medium and high cancer differentiation were 87.5%(14/16 cases),93.9%(31/33 cases) and 100%(11/11 cases),respectively.The expression of intensity was increased with the tumor cells differentiation.The ultramicrostructural changes were studied by electric microscope in 4 cases of colorectal cancer and 6 cases of colorectal adenoma with 7 healthy adults colorectal tissue as control.The mitochondrial crista were found deformed in shape and decreased in number.Many mitochondria the crista were disappeared.Some with ruptured membranes of mitochondria and herniation of matrix.Conclusion The apoptosis proceeded in the colorectal cancer is mainly through the intrinsic apoptosis pathway (mitochondria mediated pathway).Targeting treatment of intrinsic apoptosis is considered not without risk before the complete elucidation of the pathophysiology.